Halcyon is rumored to be a miracle drug–a cure-all for post-traumatic stress disorder. Inducing a state of calm amnesia, the drug helps people completely forget their fears. Those afflicted with PTSD, most notably veterans from the recent wars, will finally be able to lead normal lives. But the research process behind the medication is shadowy and filled with terrible secrets.

Dr. Sebastian Briggs, Halcyon’s inventor, was a respected professional conducting his research at UNC. During trials, the accidental death of Susan Sharpe, an undergraduate test subject, forced the university to let him go, but Briggs refused to stop testing. The scientist’s obsessive, sadistic nature pushed him to continue for his own evil enjoyment, and besides, powerful people were willing to fund his work. Briggs sets up a new lab in nearby Research Triangle Park, and gives it a sinister nickname: the Monkey House. What he does there is anyone’s guess. His funders, sensing major returns, make sure they don’t look too closely at his methods.

But what these powerful, wealthy benefactors don’t realize is that Briggs developed another drug alongside the calming Halcyon– a pill that strips away everything that makes a person human, bringing about a state of complete and total animal fear and anger. Briggs called it Seethe, and unbeknownst to UNC, he was testing this drug when Susan’s death occurred.

Ten years later, Briggs’s other test subjects, also students at the time, find themselves struggling to control their behavior. Each person finds a mysterious bottle of pills among his or her belongings, cryptically labeled take every 4 hours, or else. Somehow, all paths lead back to Dr. Briggs and his fateful experiments, and soon each is drawn to the Monkey House. They come to get answers about troubling memories that seem to stem from nowhere–Was Susan’s death really an accident? Is one of them responsible? What are the pills for? Most importantly, why are they still being affected? But Sebastian Briggs isn’t interested in providing explanations. In fact, he has one final test in mind: put his old subjects in the Monkey House, inject them with the deadly Seethe, and watch. After the lights go out, who will emerge alive?